Got a question for our Technical Editor, Doc Robinson? Email him at
We know all our readers enjoy our Tech Torq section in HEAVY DUTY every issue. So to make sure you've always got plenty of Tech Torq at your fingertips we've provided last issue's Q&A's right here.
And if you just can't get enough why not purchase our Tech Torq Handbook which is totally devoted to Tech Tips and covers just about every Harley technical issue you can think of. Click here to order yours!
Enjoy our tips!
BIG WHEEL BRAKES
G’day Doc, I really enjoy your technical column and have learnt a great deal. I was riding back home from Sydney and called into an aftermarket shop the other day and they were doing a big front wheel conversion on an Ultra. It’s something that I have been thinking of doing to my bike.
They were friendly enough but didn’t want to answer too many of my questions. I notice from the mags and websites that when they put a big wheel on baggers they usually only run one disc rotor and one caliper. Do you know why this is the case? Also, in doing that, how does it affect the operation of the ABS system?
I understand I will have to change the front guard and make some changes to the forks – using different trees, I should imagine. I’d appreciate as much information on this matter as you can provide me with. Thanks very much for your help on this one, Doc.
Hi Don, the reason for running just the one caliper is to
show off the trick front wheel that is usually...
Doc, I saw in HEAVY DUTY issue #125 that you had a Cruise-Mate throttle lock installed.
I love the idea and have used something similar before on my 2003 and 2010 FXST. When I bought my current bike, a 2011 Deluxe, it didn’t have the thumb wheel installed. I raised this with my mechanic at a local Harley-Davidson dealer and asked them to put a thumb wheel in and asked them about the Cruise-Mate.
The guys at the dealership were shocked that I would consider it but being mechanically illiterate, I asked for a simple explanation.
I was told that the wheel was an adjustment that should only be used by mechanics at service to set throttle tension. This is because if the bike is turned full lock either way with the wrong adjustment, the throttle will not release and could caused a serious safety issue. This sounded reasonable to me.
What is the go with the thumb wheel and the throttle-lock devices? Are there any issues or anything else I should be aware of?
Hi Andrew and thanks for your enquiry. Firstly, people have
been using the Harley-Davidson thumbscrew as a makeshift
cruise control for many...
I’m looking for a reputable bike builder up here in Queensland to build a bike on the lines of the Captain America bike. But I want a Softail frame because our roads up here are crap and instead of a Panhead I want an S&S Genny Shovel sort of look with a kicker and tin-style primary. I want a 38-degree rake and a 21in wheel up front with a 16-incher at the rear running a 150. The frame I want all chromed and with floorboards instead of forward controls, in particular the half moon old-school-style floorboards, so I hope you can help me out. I live in Mackay, Qld, by the way.
Gumby, there don’t seem to be too many builders up your
way that could pull off the job. Neale Brumby has...
Doc, I’m thinking of buying a new Ultra and fitting it with a 120R motor. Have you heard of anyone using the 120R for long hauls and sitting on it for a 10-15 hour day? Can you advise me as to the longevity of it? I would appreciate your comments.
John, I discussed your situation today with a buddy of mine
who works for Harley-Davidson, explaining to him why you
WIDE GLIDE HANDLING
Doc, I finally have the Harley-Davidson I used to dream about. As a child, my uncle would bring me bike magazines to look at the choppers. So, now I am astride a 2011 Wide Glide and it goes fast but the suspension is not so good. I am becoming a faster rider and want to corner better at speed. My friend said you could recommend some upgrade parts.
I’m happy that you have finally achieved your dream,
Carbon. Before you go too fast though mate, if you haven’t
Doc, back in the Shovel days we always twin-plugged our heads and a lot of us did the same on Evos too. No-one seems to do it now. Why is this? The question came up over a few beers with some mates. We presumed that better combustion chamber design makes it no longer helpful but after wandering around the web a bit tonight I thought to myself, why not go to the source of all things Harley-Davidson?
Rick, I ran your question past Mark ‘Hoody’ Hood of Hood
Motor Service, who has dual- plugged many a head back...
Doc, I bought myself an FXR to get me back on two wheels after the kids came along. It goes well enough but the belt seems to be pulling to one side. Given that I am three hours from a bike shop I thought I’d run this one by you. What’s the best way to check this and adjust if needed?
FXRs are great bikes, Pitty, and arguably one of the
best-handling Big Twins ever made. Aligning the belt is
simple with the...